Locking slider



Oct. 9, 1951 FElTL 2,571,024

LOCKING SLIDER Filed Jan. 25, 1949 FIG 2 l3 .9 I2 ;/I

Q 20 M I20 2!!! rib 4 I? INVENTOR.

RUDOLF FEITL,

Patented Oct. 9, 1951 UNITED, STAT LOCKING SLIDER Rudolf Fem, Brooklyn,N. Y., assignor to Waldes Kohinoor, 1110., Long Island City, N. Y., acorporation of New York Application January 25, 1949, Serial No. 72,573

2 Claims.

, 1 I This invention relates to improvements in locking sliders forslide fasteners, and more p ticularly to sliders of the so-calledpin-lock type for plastic slide. fasteners wherein the fastener elementsare conventionally connected to their tapes in the process of moldingthe elements. As is well known, pin-lock sliders employ a lockingmember, usually in the form of a pin integral with the pull tab orfinger piece by which the slider is actuated, the pin moving into theslider body and extending in the space between two adjacent fastenerelements when the pull tab is in its lowered or at rest position. Due tothe fact that plastic material, even of the most .resistant type, suchas nylon, is inherently more liable to distortion or dislocation thanmetal, plastic slide fasteners are especially sensitive to damagecaused, for example, by deformation or dislocation of the elements bythe locking pin. Accordingly, when it is considered that deformation ordislocation of even a single element may result in failure of the entirefastener, the use of conventional pin-locks with plastic fasteners isaccompanied by substantial'risk. 'Analysis of conventional pin-locksliders for 'metal fasteners will show that they aim at achievingmaximum locking effect, i. e. resistance to movement of the slider infastener opening direction. Hence, their locking pins are designed toextend well into the space between two fastener elements of the samestringer, so that they may abut firmly against a side wall of one ofsaid elements; usually the lower element in a fastener which opens withdownward movement of the slider. This results in the element abutted bythe locking pin being required to take strain'exerted on the stringersin crosswise direction above the slider, which tends to actuate theslider downwardly or in fastener opening direction. Such crosswisestrain is substantial if the garment to which the fastener is applied isopened by stripping the stringers apart above the slider rather than bylifting the slider pull tab to release the locking pin and thereuponpulling the slider .downwardly. In any case, the aforesaid crosswisestrain is transmitted to the locking pin and thereby to the elementagainst whose side wall the locking pin abuts.

Obviously, plastic slide fasteners or zippers are unable to withstandthe severe crosswise strain transmitted to a fastener element engaged bythe conventional locking pin as aforesaid, while at the same time thefacility and ease with which pin-lock sliders may be manufactured andoperated makes their retention as a locking means for plastic slidefasteners highly desirable.

Accordingly, it is a principal object of this invention to provide apin-lock slider designed and especially adapted for use with plasticslide fasteners which, while avoiding the transmission of heavycrosswise strain from lockingpin to plastic fastener element abuttedthereby as is likely to cause distortion or dislocation thereof,nevertheless affords a locking effect which is suflicient for slidefasteners as used in or on garments of the type to which plasticfasteners or zippers are usually applied.

More particularly, the invention aims to provide a slider of theso-called pin-lock type for use with plastic slide fasteners, whereinthe locking pin is so constructed and arranged as to abut against theupper edge corner of a fastener element, rather than against its sidewall, thus to ofier suificient protection against unintentional openingof the fastener under normal strain, but at the same time being capable,under excessive or abnormal strain, to effect a slight dislocation orshift of the engaged element so that it cannot become damaged, ordislocated with respect to its tape.

The invention also aims to provide a slider construction offering thenecessary accommodation for the slightly dislocated element asaforesaid, whereby it is further protected against deformation underexcessive strain transmitted to it through the locking pin.

The above and other objects and advantages of the invention will beapparent from the following detailed description, taken with theaccompanying drawing, of the improved pin-lock slider for plastic slidefasteners, wherein- Fig. 1 is a plan view of the improved lockingslider;

' Fig. 2 is a section taken along line 2-2 of Fig.1, illustrating therelation of locking pin and fastener element engaged thereby when thepull tab is in its lowered or at rest position; and

Fig.3 is a section similar to Fig. 2 but illustrating the pull tab inits raised or release position.

1. Referring to the drawings, a slider generally 3 which hingedlyconnects a pull tab 15 to the upper wing and hence to the slider bodyfor turning movement about a substantially fixed axis. Integral with thepull tab I5 and extending from its upper edge is a locking pin [6, saidpin being adapted, when the pull tab is in its lowered or at restposition, illustrated in Fig. 2, to extend through a window I! providedin the. upper wing II by an amount such that it lockingly engages withone of the fastener elements:

[8, as illustratively shown. As seen in Fig. 3, movement of the pull tabI5 to its raised position frees the locking pin from engagement with thefastener elements.

According to the invention, the length of the locking pin [6 is suchthat it does not extend substantially into the space between twoadjacent fastener elements, so as to firmly abut against the side wallof the lower of said elements, as is conventional. Rather, the lockingpin has. shorter length. than conventionally employed with metal slidefasteners, and. its end face is cut away to provide a surface 20 which.is inclined to the side wall l8a of any element [8 engaged thereby, withthe result that it engages against the upper edge corner of said elementrather than againstv its side wall, as shown in Fig. 2. Thus, whennormal crosswise strain is exerted on the fastener stringers above theslider, which tends to move the slider downwardly, the locking pin l6functions in normal manner, since there is sufiicient contact betweenthe inclined end face 20 of the locking pin and 4 through the simple yethighly effective expedient of purposely providing for slight shiftingmovement of the engaged fastener element upon the occurrence ofexcessive or abnormal strain.

As many changes could be made in carrying out the above constructionswithout departing from. the scope of the. invention, it is intended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

I claim:

1. A pin-lock' slider for slide fasteners of the type including a. pairof stringer tapes carrying .rows' of oppositely disposed fastenerelements along their adjacent edges, said slider comprising the upperedge corner of the element I8 engaged thereby as to prevent accidentalopening of the fastener. However, if the crosswise strain ex,- erted onthe stringers as aforesaid becomes sufficiently great as would give riseto the danger that the element engaged by the pin might be deformed ordislocated, said element will be shifted slightly to the left of itsposition shown in. Fig. 2, consequent to the wedging or camming actionapplied thereto by the inclined end face 20 of the locking pin. Toaccommodate the slight dislocating movement of the element as aforesaid,the inner face of the under wing I2 is provided with a shallow recess inwhich is sufficiently deep as to permit the slight shift aforesaid ofthe engaged element without danger of its deformation or of becomingdislocated from its tape, and whose end walls I21), I20 are slopedlongitudinally of the slider rather than being shouldered, so as tofacilitate movement of the fastener elements longitudinally through therecess.

Thus, it will be seen that a locking slider as aforesaid is especiallyadapted for use with plastic slide fasteners, the elements of which arelikely to be deformed or dislocated from their tapes under the action ofthe locking pin of binlock sliders as conventionally employed for metalslide fasteners. The described locking slider affords locking actionbetween locking pin and element engaged thereby which is adequate toprevent unintentional opening of the fastener. On the other hand, thedanger of said element being deformed, dislocated or torn from its tapeunder excessive strain is positively avoided front and rear wingsconnected by a neck portion, a pull tab hingedly connected to the frontwing for raising and lowering movement with respect thereto about afixed axis, a locking pin integral with the pull tab and adapted toextend through an opening in the front wing at predetermined limiteddistance into. thespace between adjacent fastener elements of a rowthereof dis posed within the slider when the pull tab is in its loweredposition, thereby normally to lock the slider to the fastener elementsdefining said space without displacement of said elements or of the tapecarrying the same, the end face of the locking. pin being inclined tothe pin axis and being adapted, when the pull tab is lowered asaforesaid and upon an abnormal strain being exerted on thefastenerstringers in direction tending to move the slider infastener-opening direction to engage on the front upper corner of thelower of said adjacent fastener elements and thereby to cam said elementaway from said locking pin, the inner face of the rear slider win havinga. shallow recess for accommodating said element in its movement awayfrom the locking pin, the end walls of the recess being slopedlongitudinally of the slider so as to permit relatively free movement ofthe fastener elements through the recess upon said elements beingsuccessively cammed away from the locking pin as aforesaid. 2. Apin-lock slider as set forth in claim 1, wherein the rear wing recess issufiiciently deep as to permit the fastener elements when engaged by theinclined end face of the locking pin under the condition of abnormalstrain as aforesaid to be shifted substantially out of the path of thelocking pin.

RUDOLF FEITL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,193,080 Soave Mar. 12, 19402,240,704 Lange May 6, 1941 2,267,384. Waldes Dec. 23 1941 2,287,482Marinsky June 23, 1942 2,360,437 Mikulas et a1 Oct. 17, 1944 2,529,520Mikulas Jan. 30, 1951

